purified by column chromatography on silica gel with eluent of 5:1 benzene:ethyl acetate and crystallized with n-hexane to give a yellow powder (50 mg). The powder was further recrystallized from diethyl ether / n-hexane to give crystals of diethyl 2-methyl-4- (2-trifluoromethyl-phenyl)-6-cyano-1,4-dihydropyridine-3,5-dicarboxylate. Reference: Chem Pharm Bull. 1991, 89-3201.

Page 16 of 17

The End